refs https://github.com/TryGhost/Toolbox/issues/95
- Media files uploaded through the Admin Media API should be accessible throught the frontend under `/content/media/`
- Note the feature is behind an alpha "mediaAPI" flag that has to be enabled in the labs first
refs https://github.com/TryGhost/Members/commit/9e59f5a9
Since we have a DynamicRedirectManager for handling adding/removing
redirects at runtime, we no longer need the custom-redirects middleware.
The redirects service does however need an init method now to add the
custom redirects at Ghost boot, so it's been refactored into our Class &
DI pattern.
- we're slowly trying to draw the lines between the backend and the frontend correctly
- these files deal only with serving the frontend so they should live there
- there are lots of mixed requires in these files, so having them in the right place makes that clear
